FOG Multicast on different VLANs

[sega]

Hi,

We have currently a FOG server running on VLAN 1, that unicast round about 40 pcs in VLAN 2 - 5 (not the best approach). To optimize that, I wanted to try to run multicast, but sadly our switches are just Layer 2 switches and they don’t support that on other VLAN (as far as I read, not a big network guy myself).

So my idea was now: The FOG server is running on a VM, is it possible to give that machine just 4 more virtual network adapter (for each VLAN one) and reconfigure the IP address on the clients to one thats on there VLAN? Somehow I think that would be too easy.

Or do I need to have a second FOG Server in that specific VLAN that just using the main FOG storage?

What else could I do to optimize the workflow?

Thanks in advance!

[george1421]

@sega said in FOG Multicast on different VLANs:

I wanted to try to run multicast, but sadly our switches are just Layer 2 switches and they don’t support that on other VLAN (as far as I read, not a big network guy myself).

Layer 2 switches are good enough. Hopefully they are managed switches, that will make them work a bit better. Turn on igmp snooping on the switches. What that will do for you is enable sparse mode (i.e. only ports part of the multicast will transmit multicast data) without it the switch will work in dense mode where multicast traffic will be sent to all ports (impacting the bandwidth of devices not part of the multicast).

Muticasts are typically restricted to the current vlan. Where the magic happens is on your router between the vlans. Your router needs to be configured to forward muticast traffic between the vlans. This is typically done with a igmp helper / proxy / relay service much like dhcp needs a helper service to forward dhcp traffic from remote vlans to the vlan that has the dhcp server. This service running on your router will send the multcast data between the subnets.

So my idea was now: The FOG server is running on a VM, is it possible to give that machine just 4 more virtual network adapter (for each VLAN one) and reconfigure the IP address on the clients to one thats on there VLAN? Somehow I think that would be too easy.

This won’t work because when FOG service was designed it was designed to only support a single imaging network. Your fog server can have 4 network adapters, but only one can be the imaging network adapter. The rest will only work as management interfaces.

Or do I need to have a second FOG Server in that specific VLAN that just using the main FOG storage?

If you have no other option you can use a fog storage server here on the remote vlan. The issue is that only the FOG server supports muticasts. The fog storage nodes only supports unicast imaging.